Worried - burnt rubber/but clearing up

[hammer]

This is the longest I have pushed a single pitch of yeast without reculturing a fresh slurry (WLP001) and on my last two batches (brewed one day apart with pitch from same previous batch) I noticed a burn rubber aroma from sample (coming out of the primary). My initial thought was that I was picking up some sort of phenolic and that I had stretched my yeast too long and had picked up an infection. But now the aroma has completely cleared up in one tank, and seems to be clearing in the other.

Fermentation temp had dropped a few degrees and I had to rig up some heating elements to raise the temp back into the mid 60s. So I was wondering if it wasn't just sulphur? Could the sulphur and the late hops (its a late hop IPA) belnd together to make a burnt rubber? The aroma also remonded me a but like a rubber glove, not "farty" or "burnt match".

Another thing that I noticed is it seems that the aroma seems to be clearing as the yeast drops. Could this have something to do with the yeast? The beer has now been in the primary for going on 3 weeks now as I try to figure out what to do with it. I just can't believe how much the aroma has cleared up.

I'm still hesitant to ship this beer but am thinking about bright tanking it and seeing exactly what I get. It went from what I thought was 90% positive ruined to now at least mostly hope for at least the one tank.

[South County]

Autolyzed yeast

My initial thought would be a high volume of autolyzed cells due to the re-pitching stress. Although there could be a handful of things that can generate that smell, including just a few colonies of bacteria, or something else considering the yeast seem healthy enough to mop the odor up. If you have hit your target gravity, I would drop any yeast in the cone, let it sit at 68 for 24 hours and then start crashing over 2 days, 50F one day and 36F the next, rack the rest of the yeast and transfer/filter. By then you should be good.